To provide a polyester film that excels in a clear feel for a member such as a polarizing plate in a state where release films are laminated, excels in inspectability in performing inspection by visual inspection of a defect such as a distortion or an unevenness and presence or absence of foreign matters by a crossed Nicols method, and excels in productivity.

There is provided a release film that comprises a coextrusion biaxial orientation polyester film of three or more layers, wherein at least one side surface layer contains the styrene and the divinylbenzene copolymer crosslinking particle, and at least an one side outermost layer has the silicone release layer.